Thread severing attachment for sewing machines



l :'`el"i.-23, 1932.. P. CASTAGNA v 1,846,628

-THREAD SEVERING ATTACHMENT ,FOR SEWING MACHINE$ Filed May 14, 1930 INVENToR. AiD//sqyufuf A57/mm.

ATTORNEY Patented F eb. 23, 1932 UNITED STATES PATENT OFFICE PASQ'U'ALE CASTAGNA, 0F BROOKLYN, NEW YORK SE'VEBING ATTACHMENT FOR SEWING MACHINES Application led May 14, 1930. Serial No. 452,212.

.5 erator of a sewing machine to sew a large number of articles with a chain of stitching vconnecting' the successive articles, and a special operative is then employed to sever the connectingchains. e

I am aware that thread cutters for sewing machines are known in the art, but, heretofore, such cutters have been built into the machine, or have been designed for special types of sewing machines.

It is an object of my invention to provide a very simple type of thread cutter which may be attached to an ordinary sewing machine.

Another object of my inventionis to provide a thread cutter which is operated by the '20 raising of the presser foot. v

Another ob 'ect of my inventionis to provide a cutter located close to the presser foot, so that the thread may be'cut close to the work, thereby obviating the necessity of pro- T25 viding a long chain of stitching between pieces of work.

Another object is to provide means for readily disconnecting the device whenever desired, so that the normal operation of the presser foot will not cause the cutter to operate. f

Another object of my invention is to provide a device comprising a pair of shears which are normally open and disposed transversely to the line of stitching so that the stitching will normally be fed through the open shears.

Other objects of my invention will appear inthe following description of a preferred embodiment and thereafter the novelty and scope of the invention will be pointed out in the claims. Y

In the accompanying drawings:V

Figure 1 is a view in rear elevation of my improved severing attachment applied to a sewing machine, only a portion of the latter being shown; ,i

Fig. 2 is a view of the same in sideelevation. looking from the right hand side of Fig. 1'; ,and 1 Fig. 3 is arview in section taken on the line i 3 3 of Fig. 2.

In the drawingsI showval bed plate of a sewing machine atlO with the usual needle bar 11 and presser bar 12 reciprocable in a Yhead portion 13. Secured to the lower end of the presser bar is the usual presser foot d ieneath which is the usual four-motion My improved attachment includes an ani gle bracket 16 which is, secured to the bed plate 10 by means of screws 17 Bearing against the rear face of the upright flange of the angle bracket is a iiXed blade 18. This blade is located to the rear of the presser foot and extends transversely across the line of feed of the work so 'that the work will be fed over the upper or cutting edge of the blade. rJhe blade 18 is formed with a shank portion 19 which is secured to the bracket 16 by means of two screws 20 and 21. The screw'21 serves as a pivot for an oscillating blade'22. A spring 23 is connected at one end to the blade 22, while the other end thereof is connected to an upright arm 24 projecting from the bracket 16. The spring serves to hold the blade in the open position shown in Fig. 1 with a tail piece 25 of the blade bearing against the screw 20 as a stop. Mounted on the presser bar 12 is a collar 26 which is secured to the bar at any desired position by means of a set screw 27. A link 28 connect-s the collar 26 and the tail piece 25.

The presser bar 12 is provided with any suitable means for raising and lowering the same. It will be understood that this means may be in the form of a handlever, a foot pedal or aknee shift, such means being already well 'known andA commonly used. In l the particular embodiment illustrated, I show a hand lever 30 which is pivoted to the head 13 and has a cam surface 31 which bears against an arm 32 secured to and projecting from the presser bar 12. Also bearing against the arm is a lever 33 fulcrumed on the head 13. This lever is connected by suitable means to a knee shift or pedal. However, these parts are not shown as they are well known in the art.

The upper end of the link l28 is preferably l sition that the shear blades will lie transversely acrossthe line of feed of the work and close to the rear of the presser foot. The screw 86 is then inserted in the upper hole 37 in the collar and with the presser bar in lowered position, the' collar is movedI up on the bar until the screw bears against the upper edge of the slot 35. Thereafter the collar 26 is secured to the bar by tightening the set screw 27.

The operation of the device is as follows: Normally, when operating the sewing machine, the presser foot 111 is in lowered position and the spring 23 holds the blade 22 in raised position. As the work is fed by the four-motion feed 15 it passes between the blades 22 and 18. As soon as the sewing on one piece of goods has been completed and said piece has passed the blade 22, the operator raises the presser bar 12 by means of the handle 30 or by the knee shift, as the case may be, and in raising the presser bar the blade 22 is swung downward, so that the thread is'severed between the blades 22 and 18.` While the presser foot is raisedthe operator introduces a new piece of goods thereunder and immediately drops the presser foot and resumes the sewing operation.. As soon as the presser foot drops, the blade 22 rises and the work is fedthereunder.

When it is desired to disconnect the cutter, the screw 36 is removed from the upper hole 37 and introduced into the 'lower hole 37. Then when the presser bar is raised sufcient lost motion will be provided by the slot 35 to prevent the cutter' from operating.

It will be observed that I have provided a very simple device that may be attached to any sewing` machine and which does not have to he built into the sewing machine as part of the equipment thereof. The cutter is always in position to operate and requires no special attention.` The operator may raise the presser foot with his knee as vhe introduces each new piece of work thereunder and by this act severs the previously sewn piece from the new work without having to operate the shears by hand or to guide the work manually to the shears.

It is obvious that the cutter may also be used inf connection with a continuous length of goods such-as a piece of tape which it may be desired to cut into suitable lengths. The operator can cut the tape whenever he so desfires by the mere act of raising the presser oot.

It will be noted that either or both of the shear blades may be detached from the bracket 16 to permit of sharpening them or replacing them with new blades in case of breakage. However., it will be obvious that the lower shear blade could be formed as an integral part of the bracket 16, if so desired.

IVhile I have described a specific form of my invention it will be obvious that variations may be made in construction, arrangement of parts and mode of operation and I reserve the right .to such variations as fall within the spirit and scope of the following claims.

I claim:

1. A cutting attachment for a sewing machine, comprising a pair of shear blades pivotally connected together, a spring normally holding the blades open, means for attaching one blade to the work support of the machine, and means for connecting the other blade to the presser bar of the machine, whereby when said bar is raised the latter blade will be swung downward to sever Inaterial placed between the blades.

2. A cutting attachment for a sewing machine, comprising a pair of blades pivotally connected-together, a spring normally holding theblades open, means for attaching one blade to the work support of the machine, means for connecting the other blade to the presser bar of the machine, whereby when said bar is raised Vthe latter blade will be swung downward to sever material placed between the blades, and means for `operatively disconnecting the second-named blade from the presserfbar.-

3. A cutting attachment for a sewing machine, comprising a pair of shear blades pivotally connected together, means for attaching one blade to the work support of the machine, the other blade having an extension on the opposite side of the pivot, and a link connected at one end to said extension and adapted to be connected at the other end to the presser bar of the machine, whereby when said bar is raised the second-named blade will be moved downward into cooperative-engagement with the first-named blade. i

4. A cutter attachment for a sewing machine, comprising a pair of shear blades pivotally connected together, a springnormally holding the-blades open, means forv attaching one blade to the work support-of the machine, the other blade having an extension on the opposite side of the pivot, a collar adapted to be secured to the lpresser bar and formed with two vertically spacedsthreaded holes, a pivot screw adapted to be screwed into either of said holes, and a link connected atV one'end to said extension .and having at itsopposite end a slotfadapted to' receive said screw;

5. The combination with a sewing machine Y' having a work support, a presser bar, means for raising and lowering the bar and means for feeding work under the bar, of a pair of shear blades pivotally connected together, means securing one of the blades to the Work support in such position that the blades will be disposed transversely to the line of feed, means for holding the shears normally open, and means adapted to be actuated by raising of the presser bar to close said shears.

6. The combination with a sewing machine having a work support, a presser bar, means for raising and lowering the presser bar and means for feeding work under the presser bar, of a pair of shear blades, a bracket on which the shear blades are mounted, means for securing the bracket to the work support in such position that the shears will be disposed transversely to the line of feed immediately to the rear of the presser bar, a spring holding the shear blades normally open, and means connecting one of the blades to the presser bar, whereby when the presser bar is raised the shears will be cooperatively closed.

7 The combination with a sewing machine having a work support, a presser bar, means for raising the presser bar and means for feeding work under the presser bar, of a pair of blades pivotally connected together, means for securing one o-f the blades to the work support in such position that the shears will be disposed transversely to the line of feed and immediately to the rear of the presser bar, a spring holding the shears normally open, a collar adjustable on the presser bar, and a link connecting the other of the blades to the collar, whereby when the presser bar is raised the blades will be cooperatively closed.

8. The combination with a sewing machine having a work support, a presser bar, means for raising the presser bar and means for feeding work under the presser bar, of a pair of shear blades pivotally connected together, means for securing one oftheblades to the work support in such position that the shears will be disposed transversely to the line of feed and immediately to the rear of the presser bar, a spring holding the shears normally open, a

collar adjustable on the presser bar, a link connecting the other of the blades to the collar, whereby when the presser bar is raised the blades will be cooperatively closed, and means for operatively disconnecting the second-named blade from the collar.

In testimony whereof, I have signed this specification.

PASQUALE CASTAGNA. 

